The temporary loss of memory as soon as you enter a walmart store and forget everything there was on the shopping list (even when you had meticulously made a neat mental list). Recovery occurs slowly starting exactly when you pulled out of parking all the way until you reached your home.

Irritated Wife: Did you bring all that I'd asked for?
unhappy-with-himself Husband: No, I suffered a Walmart Amnesia.
Irritated Wife: You lazy scumbag!